Dryer appliances generally include a cabinet with a drum mounted therein. In many dryer appliances, a motor rotates the drum during operation of the dryer appliance, e.g., to tumble articles located within a chamber defined by the drum. Alternatively, dryer appliances with fixed drums have been utilized. Dryer appliances also generally include a heater assembly that passes heated air through the chamber of the drum in order to dry moisture-laden articles disposed within the chamber. This internal air then passes from the chamber through a vent duct to an exhaust conduit, through which the air is exhausted from the dryer appliance. Typically, a blower is utilized to flow the internal air from the vent duct to the exhaust duct. When operating the blower may pull air through itself from the vent duct, and this air may then flow from the blower to the exhaust conduit.
One issue that exists with dryer appliances is the possibility of restrictions in, for example, the vent duct or exhaust conduit. Restrictions decrease the effective operating size of the passages through which air flows during operation, and can be caused by, for example, lint build-up or other impediments lodged in such passages. Restrictions can prevent proper airflow, thereby reducing drying of articles in the dryer appliances. In some cases, restrictions can cause damage to dryer appliances, and can even result in fires. Accordingly, the ability to diagnose restrictions is of upmost importance.
Attempts have been made to diagnose restrictions in dryer appliances. However, typically known attempts generally require substantial additional hardware to be included in the dryer appliance, which can be costly. Further, many known attempts have proven to be ineffective or inaccurate. Still further, known attempts only provide an alert that a blockage exists when cleaning is required, and cannot provide any restriction trend tracking or time estimates before cleaning is required.
Accordingly, improved dryer appliances and methods for diagnosing restrictions in dryer appliances are desired. In particular, dryer appliances and methods that provide inexpensive and effective restriction monitoring, and that can provide restriction trend tracking and time estimates before cleaning is required, would be advantageous.